Aside from cost, its getting the parts. Overnight parts from japan do not exist regardless of what Chad Lindeberg leads you to believe.
Having a skyline would be awesome, acctualy driving it would be even cooler, but regardless its just like any other old car, shits going to need to be replaced, shit will break especially if its being driven, it will be expensive, and much time will be spent waiting for the parts. Also i’m sure adam (boxersix) can chime in on how its not like calling Advance Auto, kinda gotta source shit out and make some friends overseas.